When adding a filter/slicer to the Filter pane, You can now enable/ tick the option to : "Requires single selection". Which then allows the user to only select one option from the filter. However, this option needs a little improvement as it can easily be overwrite this by doing any of the following :
- CTRL + clicking several options
- Deselecting the selected option (causing a Select All)
- Erasing the filter (causing a Select all)
There are currently on page visual slicers that fully enforce a single select (such as a Chiclet slicer) and the same behavior should be applied to filter pane filters/slicers.